Submitted to: American Society for Microbiology Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: October 16, 1997
Publication Date: N/A
Technical Abstract: Leptospira interrogans is a bacterial species that has a complex genome containing two circular chromosomal replicons. Evidence for extensive chromosomal rearrangements occurring in the larger chromosomal replicon has been obtained by comparing genetic organization of closely related L. Interrogans strains. The L. Interrogans genome contains several distinct classes of repetitive DNA, including insertion elements. We have characterized in detail two related but distinct IS3-like elements, IS1500 and IS1501. These elements are 1230 to 1236 bp long and have typical IS structure. Each element has two major open reading frames, orfA and orfB, which overlap. Potential frame shift sequences were identified, which could permit synthesis of ORFAB fusion proteins. Analysis of isogenic strains selected for antigenic variation showed that copies of both IS1500 and IS1501 resided on rearranged fragments, suggesting they may affect phenotype and play a role in generating chromosomal rearrangements.